True-Amplitude MZO in Laterally Varying Media: Experiments on Synthetic Data

The process of simulating a zero-offset (ZO) section from a given common-offset (CO) section so that primary reflections in the simulated section have the correct, (ZO) geometrical spreading, is called true-amplitude migration to zero offset (MZO). A recently proposed Kirchhoff-type, true-amplitude MZO algorithm for 2.5-dimensional models with laterally varying velocity is implemented on simple synthetic examples. The main steps of the algorithm are the construction oi"ihe stacking line and weight function for each point on the ZO section to be simulated. These include the computation of a traveltime table for construction of CO isochrones by an eikonal equation approach, as well as dynamical tracing of certain rays for each point on each isochrone. In particular, the in-plane CO isochrone curvatures are needed in the process. Comparison of the simulated ZO section with the one directly computed from the model, confirms the validity of the proposed algorithm.